X-ray diffraction from chiral molecules with twisted beams

Abstract

Structured x-rays carrying an orbital angular momentum break spatial inversion symmetry and have been proposed as a means to probe chirality. We theoretically investigate twisted non-resonant x-ray diffraction from chiral molecules and demonstrate that no dichroic signal can arise from randomly oriented molecules, irrespective of the beam spatial profile. However, a dichroic response is found to emerge if the molecule is oriented. Our results establish the beam and sample conditions for which a measurable dichroic scattering signal survives axial and focal averaging.